TEC3 and OEM equipment

[trpower7]

When using a stand alone engine management system such as the TEC3, how much of my OEM equipment can I retain. Ideally, I want to make the car function exactly as it did stock, with the exception of the engine now being run by the TEC3. This means everything, tach, speed, fuel gauge, temp gauge, A/C, P/S, Cruise, all lighting, windows, locks, the whole nine yards. In the past I've just pulled out all the ECU's sensors except the ones that go to these respective units, bundled them up and left the others attatched, and bolted the ECU somewhere else behind the dash. In essence, leaving the ECU attatched and throwing all kinds of codes, but still allowing the other units to function. I don't see why this wouldn't work on a S14, but would like to hear some personal experiences. I also believe I can fix the A/C idle up issue by wiring in the A/C power switch into one of the TEC3's spare connectors and using that signal to bump the idle up to 1K or so. Thoughts, opinions???